Coletti was trying to hang on to fourth position in the closing stages when Leimer made a passing attempt into Brooklands.
The Racing Engineering car pushed Coletti's Rapax machine into a spin and out of the race.
Leimer went on to finish fourth, a result he retains, but he will start 10 places down the order in the sprint.
A GP2 statement said: "although Coletti left enough room, Leimer still collided with him."
Caterham's Alexander Rossi also gets a 10-place penalty for a collision that ended Kevin Ceccon's race. Rossi survived to finish 10th.
Jon Lancaster was also investigated for a clash with James Calado, but did not receive a penalty.
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